This invention relates to spark plugs and, more particularly, relates to a fuel injection spark plug for use in combination with an external source of pressurized fuel for supplying gaseous fuel to an internal combustion engine.
It is known to feed a gaseous fuel such as hydrogen gas to an internal combustion engine at points in proximity to each engine spark plug using individual feed lines for each cylinder. U.S. Pat. No. 1,536,065 discloses a spark plug structure having radial openings in combination with a jacket ring for introducing a gaseous fuel for self cleaning of a spark plug.
U.S. Pat. No. 1,525,073 shows a spark plug having means for feeding exhaust gasses from the exhaust manifold of an engine to the spark plugs in order to selectively clean the points of the spark plug.
U.S. Pat. No. 1,445,655 shows a spark plug having means for feeding gaseous fuel such as acetylene or acetylene mixed with air to an engine to assist in the starting of the engine.